It helps when posting here to have the full error, so cpanm -vvv ModuleNameHere. Can you state which version of perl you are running? The fails on the matrix for windows relate to POSIX missing tzset, which may require working around, or perhaps raising the issue against Strawberry perl to add tzset support..

This is perl 5, version 30, subversion 1 (v5.30.1) built for MSWin32-x64-multi-thread

cpan> install SVG::TT::Graph::XY

 LLAP/SVG-TT-Graph-1.02.tar.gz
  C:\STRAWB~1\c\bin\gmake.exe -- OK
Running make test for LLAP/SVG-TT-Graph-1.02.tar.gz
"C:\Strawberry\perl\bin\perl.exe" "-MExtUtils::Command::MM" "-MTest::H
+arness" "-e" "undef *Test::Harness::Switches; test_harness(0, 'blib\l
+ib', 'blib\arch')" t/*.t
t/01_main.t ............ ok
t/02_basic.t ........... 1/85 POSIX::tzset not implemented on this arc
+hitecture at blib/lib/SVG/TT/Graph/TimeSeries.pm line 582, <DATA> lin
+e 593.
# Looks like your test exited with 255 just after 72.
t/02_basic.t ........... Dubious, test returned 255 (wstat 65280, 0xff
+00)
Failed 13/85 subtests
t/03_methods.t ......... ok
t/author-no-tabs.t ..... skipped: these tests are for testing by the a
+uthor
t/author-pod-syntax.t .. skipped: these tests are for testing by the a
+uthor

Test Summary Report
-------------------
t/02_basic.t         (Wstat: 65280 Tests: 72 Failed: 0)
  Non-zero exit status: 255
  Parse errors: Bad plan.  You planned 85 tests but ran 72.
Files=5, Tests=178,  1 wallclock secs ( 0.00 usr +  0.01 sys =  0.01 C
+PU)
Result: FAIL
Failed 1/5 test programs. 0/178 subtests failed.
gmake: *** [Makefile:884: test_dynamic] Error 255
Lockfile removed.
  LLAP/SVG-TT-Graph-1.02.tar.gz
  C:\STRAWB~1\c\bin\gmake.exe test -- NOT OK
//hint// to see the cpan-testers results for installing this module, t
+ry:
  reports LLAP/SVG-TT-Graph-1.02.tar.gz
Stopping: 'install' failed for 'SVG::TT::Graph::XY'.
Failed during this command:
 LLAP/SVG-TT-Graph-1.02.tar.gz                : make_test NO
[download]

Looks like you guessed it:

t/02_basic.t ........... 1/85 POSIX::tzset not implemented on this arc
+hitecture at blib/lib/SVG/TT/Graph/TimeSeries.pm line 582, <DATA> lin
+e 593.
# Looks like your test exited with 255 just after 72.
t/02_basic.t ........... Dubious, test returned 255 (wstat 65280, 0xff
+00)
[download]

I'll try emailing Strawberry and see if they have anything to say. Thanks!

More info: rt://131606, https://github.com/ranguard/svg-tt-graph/pull/31.

I can think of a work around to patch the module to support Windows, but won't have access to a Windows machine until the weekend. I've made a note to dig deeper I to the Strawberry build/tzset issue.

Got some info from the Strawberry folks {not the developers about fixing it, but someone else at cpan mentioning the problem}:

"tzset" is common Perl command which our MIDAS scheduling software utilizes when calculating times and time zones.

...

We understand that from around June 2010, tzset is no longer recognized or implemented in Strawberry Perl. We have no idea why this is the case, as there is very little information available from the developers of Strawberry Perl. It is unknown whether this is just a bug/glitch in Strawberry Perl, or if this common functionality has been permanently and intentionally removed.

I'm guessing that, since it is now a decade later and no tzset, that it has been permanently removed. I wonder if there's a workaround? tzset seems simple enough:

"tzset" This is identical to the C function "tzset()" for setting the current timezone based on the environment variable "TZ", to be used by "ctime()", "localtime()", "mktime()", and "strftime()" functions.

But what's amusing {perhaps} I can't find a man page for the C tzset() function on my system {Ubuntu 18.04.3}